Abstract: Metalloplastic flexible annular joint, wherein it comprises a first metal ring constituted by an inner metal spring with contiguous turns closed on itself and surrounding said spring, at least one metal envelope in which is embedded the spring, said envelope being extended by two parallel planar faces which extend in a transverse equatorial plane of symmetry of the joint, said faces having flared extensions moving away from said plane at a predetermined distance from the spring to partly surround a second solid elastomer plastic ring which is coaxial to the spring in such a way as to create between the two rings a sealed enclosure of limited volume which can be used for controlling the sealing of the joint.

Abstract: Flexible annular joint having on the one hand a central core constituted by a helical spring made from metal wire with contiguous coils, which is closed on itself and in the inoperative state has the shape of a continuous ring, and on the other hand at least one envelope surrounding the central core and having in the inoperative state a cross-section formed by a curve which is not closed on itself. The internal helical spring comprises at least one continuous wire whose cross-section is a circular segment whose angle at the center is between 180.degree. and 360.degree., the chord of said segment producing the outer surface of said spring.